of chlorine and carbon , &c. 
An evident action bad taken place, and the oxygen evolved, 
meeting with the liberated carbon, would produce the car- 
bonic oxide. This experiment has been repeated several 
times with the same results. 
When the perchloride of carbon is heated with metallic 
oxides, different results are produced according to the proper- - 
tions of oxygen in the oxides. The peroxides, as of mercury, 
copper, lead, and tin, produce chlorides of those metals, 
and carbonic acid ; and the protoxides, as those of zinc, lead, 
&c. produce also chlorides ; but the gaseous products are 
mixtures of carbonic acid and carbonic oxide. I have fre- 
quently perceived the smell of phosgene gas on passing the 
chloride over oxide of zinc ; and as the substance easily libe- 
rates chlorine at high temperatures, it will be readily seen 
how a small portion of that gas may be formed. It also 
happens, sometimes, that the protoxides become blackened 
from the deposition of charcoal. 
When the vapour of the chloride is passed over lime, 
baryta, or strontia, heated red hot, a very vivid combustion is ' 
produced. The oxygen and the chlorine change places, and 
both the metals and the carbon are burnt. Chlorides are 
produced, carbonic acid is formed and absorbed by the unde- 
cornposed parts of the earths, and carbon is deposited. In 
these experiments no carbonic oxide is produced. When 
passed over magnesia, there is no action on the earth, but the 
perchloride of carbon is converted by the heat into proto- 
chloride. 
In these experiments with the oxides no trace of water 
could be perceived. 
Having thus far described the properties of the substance, 
